從特定表中獲取實體框架錯誤“無效的列名”

Question

我的EF6（代碼優先）應用程序中包含以下代碼行：

var priceDetail = context.PriceLists.Include(pl => pl.PriceDetails).FirstOrDefault();

我的目標是檢索第一個PriceList對象，其中包含PriceDetail的集合。

當該行執行時，我收到此錯誤：

-- Failed in 12 ms with error: Invalid column name 'Order_OrderNumber'.

這對我來說很奇怪，因為PriceList和PriceDetail對象都沒有引用Order對象。 這是PriceList對象：

[Table( "dbo.PriceList" )]
public class PriceList
{
    public int PriceListId { get; set; }

    [StringLength( 150 )]
    [Display( Name = "PriceList name" )]
    public string PriceListDesc { get; set; }

    public virtual ICollection<PriceListDetail> PriceDetails { get; set; }
}

這是PriceDetail對象：

[Table( "dbo.PriceDetail" )]
public class PriceDetail
{
    [ColumnDesc( "Primary key" )]
    public int PriceDetailId { get; set; }

    [ForeignKey( "PriceList" )]
    public int PriceListId { get; set; }
    public PriceList PriceList { get; set; }

    [ForeignKey( "Item" )]
    public int ItemNumber { get; set; }
    public Item Item { get; set; }

    public Decimal Price { get; set; }

    public Decimal? CostMultiplier { get; set; }
}

EF生成的完整SQL查詢如下：

SELECT 
    [Project1].[PriceListId] AS [PriceListId], 
    [Project1].[PriceListDesc] AS [PriceListDesc], 
    [Project1].[C1] AS [C1], 
    [Project1].[PriceDetailId] AS [PriceDetailId], 
    [Project1].[PriceListId1] AS [PriceListId1], 
    [Project1].[ItemNumber] AS [ItemNumber], 
    [Project1].[PriceList] AS [PriceList], 
    [Project1].[Order_OrderNumber] AS [Order_OrderNumber]
    FROM ( SELECT 
        [Limit1].[PriceListId] AS [PriceListId], 
        [Limit1].[PriceListDesc] AS [PriceListDesc], 
        [Extent2].[PriceDetailId] AS [PriceDetailId], 
        [Extent2].[PriceListId] AS [PriceListId1], 
        [Extent2].[ItemNumber] AS [ItemNumber], 
        [Extent2].[PriceList] AS [PriceList], 
        [Extent2].[Order_OrderNumber] AS [Order_OrderNumber], 
        CASE WHEN ([Extent2].[PriceDetailId] IS NULL) THEN CAST(NULL AS int) ELSE 1 END AS [C1]
        FROM   (SELECT TOP (1) [c].[PriceListId] AS [PriceListId], [c].[PriceListDesc] AS [PriceListDesc]
            FROM [Admin].[PriceList] AS [c] ) AS [Limit1]
        LEFT OUTER JOIN [Admin].[PriceDetail] AS [Extent2] ON [Limit1].[PriceListId] = [Extent2].[PriceListId]
    )  AS [Project1]
    ORDER BY [Project1].[PriceListId] ASC, [Project1].[C1] ASC

為什么會出現此錯誤？

Answer 1

我終於想通了。 在我的Order對象中，我有以下代碼行：

public ICollection<PriceDetail> PriceDetails => AssignedLocation?.LocationDetail?.PriceList?.PriceDetails;

純粹是為了方便起見，因此訂購對象可以更輕松地到達子子子類。

由於某種原因，我沒有完全理解，實體框架將其解釋為意味着PriceDetail表和Order表之間存在某種關系，從而導致上述查詢。

解決方案非常簡單：

[NotMapped]
public ICollection<PriceDetail> PriceDetails => AssignedLocation?.LocationDetail?.PriceList?.PriceDetails;

添加此屬性足以取消混淆實體框架。